Claude Sonnet 4.5 vs GPT OSS 120B

Compare Claude Sonnet 4.5 by Anthropic against GPT OSS 120B by OpenAI, in 25 community votes, claude sonnet 4.5 wins 70% of head-to-head duels, context windows of 200K vs 131K, tested across 38 shared challenges. Updated February 2026.

In 25 community votes, Claude Sonnet 4.5 wins 70% of head-to-head duels. Claude Sonnet 4.5 leads in Reasoning, Image Generation. Based on blind community voting from the RIVAL open dataset of 25+ human preference judgments for this pair.

Web Design: Claude Sonnet 4.5 and GPT OSS 120B are tied
Reasoning: Claude Sonnet 4.5 wins 71% of votes
Image Generation: Claude Sonnet 4.5 wins 100% of votes
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